Pneumonia plays an important role in children’s morbidity and mortality. In Brazil, epidemiological and social changes occurred concomitantly with the universal introduction of the 10-valent pneumococcal conjugate vaccine.This study identified risk factors for pneumonia.
A hospital-based, case-control study involving incident cases of pneumonia in children aged 1-59 months was conducted between October 2010 and September 2013 at a tertiary hospital in northeastern Brazil. The diagnosis of pneumonia was based on the WHOcriteria.The control group children admitted to the day-hospital ward for elective surgery. Children with comorbidity were excluded. The risk factors finvestigated were among those classified the WHO as definite, likely and possible. A multivariate analysis was performed.
The study evaluated 452 children in the case group and 407 in the control group. Household crowding (OR=2.08) and not having been vaccinated against the influenza virus (OR=3.7) were the only factors found to increase the likelihood of pneumonia. Being male constituted a protective factor (OR=0.52).
The risk factors for pneumonia underwent changes that were probably associated with the expansion of the vaccination program and social improvements; however, these proved insufficient to overcome inequalities.The possible protection provided by the influenza vaccine needs to be evaluated against new etiological studies.